#!/usr/bin/env python
#
# vim:ts=2:et:sw=2:ai
# Wireless Leiden configuration generator, based on yaml files'
# Rick van der Zwet <info@rickvanderzwet.nl>
import cgi
import glob
import os
import socket
import string
import subprocess
import sys
import time
import yaml

__version__ = '$Id: gformat.py 8242 2010-08-07 14:35:43Z rick $'


files = [ 
    'authorized_keys',
    'dnsmasq.conf',
    'rc.conf.local',
    'resolv.conf',
    'wleiden.yaml'
    ]

def print_title():
  print "Title view"
  print nodelist


def print_node(node):
  print "\n".join(files)

def generate_header(ctag="#"):
  return """\
%(ctag)s 
%(ctag)s DO NOT EDIT - Automatically generated by 'gformat'
%(ctag)s Generated at %(date)s by %(host)s
%(ctag)s 
""" % { 'ctag' : ctag, 'date' : time.ctime(), 'host' : socket.gethostname() }

def parseaddr(s):
  f = s.split('.')
  return (long(f[0]) << 24L) + \
    (long(f[1]) << 16L) + \
    (long(f[2]) << 8L) + \
    long(f[3])

def showaddr(a):
  return "%d.%d.%d.%d" % ((a >> 24) & 0xff, (a >> 16) & 0xff, (a >> 8) & 0xff, a & 0xff)

def netmask2subnet(netmask):
  return showaddr(0xffffffff & (0xffffffff << (32 - int(netmask))))

def generate_dnsmasq_conf(datadump):
  output = generate_header()
  output += """\
# DHCP server options 
dhcp-authoritative
dhcp-fqdn
domain=dhcp.%(nodename_lower)s.%(domain)s
domain-needed
expand-hosts

# Low memory footprint
cache-size=10000
  \n""" % datadump

  for iface_key in datadump['iface_keys']:
    output += "## %(interface)s %(desc)s\n" % datadump[iface_key]

    try:
      (dhcp_start, dhcp_stop) = datadump[iface]['dhcp'].split('-')
      (ip, netmask) = datadump[iface_key]['ip'].split('/')
      datadump[iface_key]['subnet'] = netmask2subnet(netmask)
    except AttributeError:
      output += "# not autoritive\n\n"
      continue

    dhcp_part = ".".join(ip.split('.')[0:3])
    datadump[iface_key]['dhcp_start'] = dhcp_part + "." + dhcp_start
    datadump[iface_key]['dhcp_stop'] =  dhcp_part + "." + dhcp_stop
    output += "dhcp-range=%(interface)s,%(dhcp_start)s,%(dhcp_stop)s,%(subnet)s,24h\n\n" % datadump[iface_key]
  
  return output

def generate_rc_conf_local(datadump):
  output = generate_header("#");
  output += """\
hostname='%(nodetype)s%(nodename)s.%(domain)s'
location='%(location)s' 
""" % datadump
  
  # TProxy configuration
  output += "\n"
  try:
    if datadump['tproxy']:
      output += """\
tproxy_enable='YES'
tproxy_range='%(tproxy)s'
""" % datadump
  except KeyError:
    output += "tproxy_enable='NO'\n"
  

  output += '\n'
  # lo0 configuration:
  # - 172.32.255.1/32 is the proxy.wleiden.net deflector
  # - masterip is special as it needs to be assigned to at 
  #   least one interface, so if not used assign to lo0
  addrs_list = { 'lo0' : ["127.0.0.1/8", "172.31.255.1/32"] }
  iface_map = {'lo0' : 'lo0'} 
  if not any([datadump[iface_key]['ip'].startswith(datadump['masterip']) \
    for iface_key in datadump['iface_keys']]):
    lo0_addrs.append(datadump['masterip'] + "/32")

  wlan_count = 0
  for iface_key in datadump['iface_keys']:
    ifacedump = datadump[iface_key]
    interface = ifacedump['interface']
    # By default no special interface mapping
    iface_map[interface] = interface

    # Add interface IP to list
    if addrs_list.has_key(interface):
      addrs_list[interface].append(ifacedump['ip'])
    else:
      addrs_list[interface] = [ifacedump['ip']]

    # Alias only needs IP assignment for now, this might change if we
    # are going to use virtual accesspoints
    if "alias" in iface_key:
      continue

    # XXX: Might want to deduct type directly from interface name
    if ifacedump['type'] in ['11a', '11b', '11g', 'wireless']:
      # Create wlanX interface
      ifacedump['wlanif'] ="wlan%i" % wlan_count 
      iface_map[interface] = ifacedump['wlanif']
      wlan_count += 1

      # Default to station (client) mode
      ifacedump['wlanmode'] = "sta"
      if ifacedump['mode'] in ['master']:
        ifacedump['wlanmode'] = "ap"
      # Default to 802.11b mode
      ifacedump['mode'] = '11b'
      if ifacedump['type'] in ['11a', '11b' '11g']:
        ifacedump['mode'] = ifacedump['type'] 

      if not ifacedump.has_key('channel'):
        if ifacedump['type'] == '11a':
          ifacedump['channel'] = 36
        else:
          ifacedump['channel'] = 1

      # Allow special hacks at the back like wds and stuff
      if not ifacedump.has_key('extra'):
        ifacedump['extra'] = 'regdomain ETSI country NL'

      output += "wlans_%(interface)s='%(wlanif)s'\n" % ifacedump
      output += ("create_args_%(wlanif)s='wlanmode %(wlanmode)s mode " +\
        "%(mode)s ssid %(ssid)s channel %(channel)s %(extra)s'\n") % ifacedump
        
    elif ifacedump['type'] in ['ethernet', 'eth']:
      # No special config needed besides IP
      pass
    else:
      assert False, "Unknown type " + ifacedump['type']

  # Print IP address which needs to be assigned over here 
  output += "\n"
  for iface,addrs in sorted(addrs_list.iteritems()):
    output += "ipv4_addrs_%s='%s'\n" % (iface_map[iface], " ".join(addrs))

  return output

def get_yaml(item):
  gfile = item + '/wleiden.yaml'
  gfile = 'test.yaml'

  f = open(gfile, 'r')
  datadump = yaml.load(f)
  f.close()

  return datadump

def generate_resolv_conf(datadump):
  output = generate_header("#");
  output += """\
search wleiden.net
# Try local (cache) first
nameserver 127.0.0.1

# Proxies are recursive nameservers 
# needs to be in resolv.conf for dnsmasq as well
""" % datadump
  
  # proxyX sorting based on X number
  proxies = sorted(glob.glob("proxy*"),
              key=lambda name: int(''.join([c for c in name if c in string.digits])),
              cmp=lambda x,y: x - y)

  for proxy in proxies:
    proxy_ip = get_yaml(proxy)['masterip']
    output += "nameserver %-15s # %s\n" % (proxy_ip, proxy)
  return output


def generate_wleiden_yaml(datadump):
  """ Special formatting to ensure it is editable"""
  output = "# Genesis config yaml style\n" 
  output += "#\n"
  iface_keys = [elem for elem in datadump.keys() if elem.startswith('iface_')]
  for key in sorted(set(datadump.keys()) - set(iface_keys)):
    output += "%s: %s\n" % (key, datadump[key])
  
  output += "\n\n"
  
  for iface_key in sorted(iface_keys):
    output += "%s:\n" % iface_key
    output += yaml.dump(datadump[iface_key], default_flow_style=False)
    output += "\n\n"

  return output


def print_config(node, config):
  try:
    # Load config file
    datadump = get_yaml(node)
    
    if config == 'wleiden.yaml':
      print generate_wleiden_yaml(datadump)
      return

    # Preformat certain needed variables for formatting
    if not datadump.has_key('domain'):
      datadump['domain'] = 'wleiden.net'
    datadump['nodename_lower'] = datadump['nodename'].lower()
    datadump['iface_keys'] = sorted([elem for elem in datadump.keys() if elem.startswith('iface_')])

    if config == 'authorized_keys':
      f = open("global_keys", 'r')
      print f.read()
      f.close()
    elif config == 'dnsmasq.conf':
      print generate_dnsmasq_conf(datadump)
    elif config == 'rc.conf.local':
      print generate_rc_conf_local(datadump)
    elif config == 'resolv.conf':
      print generate_resolv_conf(datadump)
    else:
      assert False, "Config not found!"   
  except IOError, e:
    print "[ERROR] Config file not found"

nodelist = glob.glob("CNode*")

form = cgi.FieldStorage()
if form.getvalue("action") == "update":
  print "Refresh: 5; url=%s" % os.environ['SCRIPT_NAME']
  print "Content-type:text/plain\r\n\r\n",
  print "[INFO] Updating subverion, please wait..."
  print subprocess.Popen(['svn', 'up', '/home/rvdzwet/wleiden/genesis/nodes'], stderr=subprocess.STDOUT, stdout=subprocess.PIPE).communicate()[0],
  print "[INFO] All done, redirecting in 5 seconds"
  sys.exit(0)

print "Content-type:text/plain\r\n\r\n",
uri = os.environ['PATH_INFO'].strip('/').split('/')
if not uri[0]:
  print_title()
elif len(uri) == 1:
  print_node(uri[0])
elif len(uri) == 2:
  print_config(uri[0], uri[1])
else:
  assert False, "Invalid option"

sys.exit(0)